The present invention relates to a switch device used in a starter for starting an internal combustion engine.
A conventional starter switch device includes a plunger axially movable and a solenoid for driving this plunger as seen, for example, in Japanese Patent Publication No. 21104/83. The plunger is disposed on the inner peripheral side of the solenoid. The plunger is provided at one end thereof with a movable contact which is adapted to abut on fixed contacts, and engages at the other end thereof with a lever which is adapted to thrust out a pinion toward the ring gear side of an internal combustion engine. In this arrangement, by the application of an electric current to the solenoid, the plunger moves in its axial direction. The thus axially moved plunger thrusts out the pinion while making the movable contact abut on the fixed contacts, so that an electric current is supplied to a starter motor and the pinion is engaged with the ring gear to start the internal combustion engine.
According to such a conventional arrangement as described above, however, the solenoid requires a certain axial length since the plunger is axially moved to move the pinion to the ring gear side by means of an attracting force of the solenoid. Inevitably, the switch device is increased in axial size. Further, the plunger receiving magnetic flux of the solenoid requires a certain cross-sectional area in order to obtain a necessary attracting force, so that there exist a problem that the switch device is also radially increased in size.